Container securing means for transport carrier with automatic latch to accommodate various clearances with bottom container fittings

ABSTRACT

The spring-biased latches on a transport carrier for automatically engaging and disengaging bottom corner container fittings are bodily movable to maintain the same latching engagement within limits for various clearances between the container fittings and the housings secured to the transport carrier on which the latches are mounted.

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[ 54 CONTAINER SECURING MEANS FOR Primary Examiner- Drayton E. HoffmanTRANSPORT CARRIER WITH AUTOMATIC Lockwood LATCH D0 ACCOMMODA'I'E VARIOUSCLE CES BmOM CONTAINER ABSTRACT: The spring-biased latches on atransport carrier for automatically engaging and disengaging bottomcorner C Drawing Figs container fittings are bodily movable to maintainthe same 105/366 D, latching engagement within limits for variousclearances 105/366 C, 248/361 A, 248/119 R between the containerfittings and the housings secured to the [51] Int. 861d /00 transportcarrier on which the latches are mounted.

PATENTED SEP1 419m SHEET 1 OF 6 PATENTEU SEP 1 419?:

SHEET 2 OF 6 PATENIED SEPI 412m SHEET 3 OF 6 PATENTEU SEP 1 4197| SHEETE OF 6 CONTAINER SECURING MEANS FOR TRANSPORT CARRIER WITH AUTOMATICLATCI-I TO ACCOMMODATE VARIOUS CLEARANCES WITII BOTTOM CONTAINERFITTINGS This invention is an improvement over the constructiondisclosed in US. Application Ser. No. 886,489, filed Dec. 19,1969.

Because of variations in the distances apart that occur between bottomcontainer fittings and container latching mechanisms on a transportcarrier spaced apart to receive these fittings, substantial clearancesmay be present. When the container is offset somewhat from a centralposition there is the possibility that the required latching engagementalong one side may be absent. As a result the container may be blown offof the transport carrier or it may bounce ofi' under certaincircumstances.

Accordingly, among the objects of this invention are: To provide formaintaining latching engagement with container fittings at the bottom ofa container on a transport carrier, such as a railway flatcar, wherethere is substantial clearance between the fittings and the latchingmechanism; to provide for automatic variation in the positions of thelatches on opposite sides of the container to maintain the same extentof latching engagement with the container fittings on these oppositesides within the limits of latching engagement with the containerfittings on these opposite sides within the limits of predeterminedclearance between the fittings and the latching mechanism individualthereto; for this purpose to mount each latch for bodily movement withrespect to the latch housing on the transport carrier; to mounttranslatorily on each latch housing a latch follower for pivotallysupporting a springbiased latch; to bias the latch follower toward acontainer fitting located on the latch housing; and to mount the latchon the latch follower to pivot about one axis against the action of abiasing spring when the container is lowered into latching position onlatch housings mounted on the transport carrier and to pivot aboutanother axis against the action of the biasing spring when the containeris lifted from the transport carrier.

According to this invention latch housings are mounted on a transportcarrier to receive rectangular containers having at the lower comer ofeach an apertured container fitting. On each latch housing there istranslatorily mounted a latch follower that is biased toward therespective container fitting and has an extent of movement equal to orgreater than the expected clearances between the container fittings andthe respective latch housings. Mounted to pivot about two axes on eachlatch follower under the influence of a relatively strong spring is alatch having a nose portion for entering the aperture of the respectivecontainer fitting. The arrangement is such that, within the expectedclearances, the nose portions of the latches on opposite sides of thecontainer will enter the respective apertures of the container fittingsto the same extent. Thus there is no likelihood that one or the other ofthe latches will move out of the latching engagement with its containerfitting.

In the drawings:

FIG. 1 is a perspective view of a portion of the deck or floor of atransport carrier such as railway car adapted to receive the containerlatching devices in which the present invention is embodied.

FIG. 2 is a perspective view of a corner fitting which is typical of thecorner fittings that are located at each of the four bottom corners ofcontainer adapted to be transported by the railway car.

FIG. 3 is a view at an enlarged scale and in side elevation of acontainer locking mechanism or pedestal taken looking generally alongline 33 of FIG. 1.

FIG. 4 is a view in end elevation of the pedestal or container lockingmechanism of FIG. 3 taken generally along 4-4 of that figure.

FIG. 5 is a top plan view of the container locking means shown in FIG.3.

FIG. 6 is a horizontal-sectional view taken generally along line 66 ofFIG. 7.

FIG. 7 is a vertical-sectional view taken generally along line 7-7 ofFIG. 5.

FIG. 8 is a vertical-sectional view taken generally along line 8-8 ofFIG. 7.

FIG. 9 is a perspective rear view of a portion of the follower.

FIG. 10 is a perspective front view of the follower shown in FIG. 9.

FIG. 11 is a view, in side elevation, of the latch.

FIG. 12 is a side elevation of the latch shown in FIG. 11 lookinggenerally along line l2l2.

FIG. 13 is a view in side elevation of the follower and latch inlatching position.

FIG. 14 shows the relation between the latch and the follower as thecontainer fitting is lowered into latching engagement.

FIG. 15 is a view, similar to FIG. 14, showing the relation between thelatch and the follower when the container fitting is lifted from thetransport position.

In FIG. 1 reference character 10 designates, generally, a portion of atransport carrier, such as a railway car, having a floor deck 11 may beformed of steel plate. The floor or deck 1 l is provided with lengthwiseextending slots 12 having transverse openings 13 and notches 14 atvarious positions therealong the purpose of which will be apparentpresently. Slidably mounted along the slots 12 are container lockingmeans each of which is indicated, generally, at 15. The containerlocking means 15 are arranged to be of identical construction except forleft and right arrangements as will be understood readily. Also thereare two container locking means 15 near each end of the floor or deck 11which are not slidable. It will be understood that four of the containerlocking means 15 are arranged to receive a rectangular container aportion of which is indicated at 16 in FIG. 2. It will be understoodalso that a number of containers 16 are arranged to be carried by thetransport carrier I0 and that, while each has the same nominal width,they may vary in length. Because of variations in lengths thelongitudinal slots 12 are provided and certain of the container lockingmeans 15 are slidable therealong to different positions.

At each of the four lower corners of the rectangular containers 16 thereis provided a hollow bottom container fitting that is indicated,generally, at 17 in FIG. 2. The container fitting 17 has a vertical slotor latch receiving opening 18 in one sidewall 19 that faces outwardly ofthe container 16. The fitting 17 also includes another sidewall 20 inwhich a circular opening 21 is located. The walls 19 and 20 extend atright angles to each other and are connected by a bottom wall 22 inwhich a slot 23 is located. As will appear hereinafter provision is madefor latching engagement with the container fitting [7 through the use ofthe vertical slot or latch receiving opening 18in the wall 19.

In FIG. 1 the distance between oppositely located container lockingmeans 15 is indicated at 24. This distance may vary slightly. Also thedistance between the sidewalls 19 of opposite container fittings 17 mayvary slightly. In certain instances where the position of the container16 varies from a central location between the container locking meansI5, there is a possibility that the clearance may be so great that thelatch intended to enter the vertical slot 18 in one side of the bottomcontainer fitting 17 may become entirely disengaged. When this occursthe corresponding side of the container 16 is not latched to thetransport carrier 10. In the event that there is a substantial crosswind or the transport carrier 10 is subject to severe bouncing due touneven trackage, it is entirely possible under these circumstances thatthe container 16 will be blown off of the transport carrier 10 or willbounce off of it. It is to overcome this problem that this invention isparticularly addressed.

In FIGS, 3-8 there is indicated, generally, at 26 a latch housing thatmay be a malleable iron casting. The latch housing 26 is provided withvertical walls 27 and 28 that are arranged to overlie, respectively, thesidewalls l9 and 20 of the bottom container fitting 17. The verticalwalls 27 and 28 are positioned at right angles to each other and betweenthem and below their upper edges is a floor 29 that is arranged toreceive the bottom wall 22 of the container fitting 17. A cover wall 30is spaced from the vertical wall 27 by laterally extending walls 31, 32and 33, FIG. 6, and is provided with edges 34 and 35 for overlying theedges of the transverse opening 13 into which the respective containerlocking means can be swung to inoperative position. A wall 36, FIGS. 4and 7, opposite cover wall 30 and depending from the floor 29 has alower wall section 37 that extends through the respective slot 12 andterminates in a trunnion that is indicated. generally, at 38. Thetrunnion 38 is provided to facilitate swinging of the respectivecontainer locking means 15 into one of the transverse openings 13. Alsodepending from the underside of the latch housing 26 is a shear lug 39that is arranged to enter one of the notches 14 to position therespective container locking means 15 along the respective slot 12depending upon the length of the container that is to be accommodated.Wings 40 and 41 extend laterally from opposite sides of the trunnion 38and underlie the edges of the respective slot 12 for the purpose ofholding the container locking means 15 against upward movement. In FIG.3 a slot 42 is shown in the cover wall 30 for receiving a tool to liftthe container locking means 15 from the retracted or inoperativeposition in one of the transverse openings 13.

In FIG. 4 there is indicated at 43 clearance that may occur between thesidewall 19 of the bottom container fitting 17 and the respectivevertical wall 27 of the latch housing 16 which forms a part of thecontainer locking means 15. This clearance 43 may be greater or less butfor illustrative purposes the particular extent is as shown in FIG. 4.FIG. 7 illustrates a condition in which there is no clearance betweenthe sidewall 19 and the juxtaposed vertical wall 27 of the respectivelatch housing 26.

In accordance with this invention provision is made for maintaining thesame latching engagement with the vertical slot 18 in the wall 19 of thebottom container fitting 17 regardless of variations in the clearanceindicated at 43. For this purpose follower means in the form of afollower, indicated generally at 44 in FIGS. 9 and 10 is employed. Thefollower 44 may be a casting of suitable metal and is bifurcated withdepending furcations 45 having apertures 46 intermediate their ends. Theapertures 46 are provided for receiving a roll pin 47, FIG. 4. The rollpin 47 is fixed to the furcations 45 and its ends extend into horizontalslots 48 that are provided in walls 49 and 50, FIG. 3, of the latchhousing 26. In this manner the follower 44 is translatorily mounted onthe latch housing 26. At the lower distal ends of the furcations 45laterally extending shoulders 51 are formed for a purpose that presentlywill be apparent. At the upper distal end of the follower 44 a noseportion 52 is provided having a surface 53 that is arranged to engagethe outer surface of the sidewall 19 of the bottom container fitting l7.Along its upper side the nose portion 52 has an inclined striker surface54 that is arranged to be engaged by the lower comer of the bottomcontainer fitting 17 as it is lowered onto the floor 29 for facilitatingdisplacing of the follower 44. Also provided at the upper distal end ofthe follower 44 are spring sockets 55 that are arranged to receive coilcompression springs 56, FIGS. 5 and 6, which are employed for biasingthe follower 44 outwardly and its surface 53 into engagement with thesurface of the sidewall 19. As shown in FIG. 6 the coil compressionsprings 56 react against the bottoms of the spring sockets 55 and theinner side of the cover wall 30 where they are held in position byinwardly extending bosses 57.

The inward movement of the follower 44 under the biasing action of thecoil compression springs 56 is limited by stop means. The stop meanscomprise bottom walls 58 of the spring sockets 55 and rear surfaces 59of the vertical wall 27.

It will be noted in FIGS. 3 and 6 that a vertical slot 60 if provided inthe cover wall 30 for receiving the furcations 45 of the bifurcatedfollower 44. A slot 60' in wall 27 receives the nose portion 52therethrough.

For latching engagement with the latch receiving opening 18 in thesidewall 19 of the bottom container fitting 17 latch means in the formof a bellcrank, indicated generally at 61. is employed. Its constructionis shown more clearly in FIGS. 11 and 12. The latch means 61 is mountedon the follower 44 for relative pivotal movement about two axes and alsofor translatory movement therewith. The latch means 61, as indicated, isin the form of a beilcrank and includes an upper arm 62 and a lower arm63 having an arcuate slot 65 at the junction between these arms. Thecenter of curvature of the arcuate slot 65 is indicated at 66 which alsois located along the pivot axis of trunnions 67 that extend laterallyfrom opposite sides of the latch means 61. As shown in FIG. 13, forexample, the trunnions 67 are arranged to engage the shoulders 51 on thelower distal ends of the furcations 45 of the follower 44. Thisengagement takes place while the bottom container fitting 17 is beinglowered into latching position and while the latch means 61 remains inlatching engagement with the vertical slot 18 of the respective bottomcontainer fitting 17.

Again referring to FIG. 11 it will be observed that the lower arm 63 hasan extension 70 which is provided with a slot 71 having a bar 72thereacross. The bar 72 and the slot 71 are provided for receiving theupper end 73 of a coil tension spring 74 that is employed for biasingthe latch means 61 into latching engagement with the respective bottomcontainer fitting 17. The lower end 75, FIG. 8, of the tension spring 75is anchored to a transverse pin 76 the ends of which are located in andheld by slots 77 in the latch housing 26.

At its upper end the upper arm 62 of the latch means 61 has a noseportion 80 which overlies the nose portion 52 of the follower 44. Thenose portion 80 has an inclined striker surface 81 to facilitatedisplacement of the latch means 61 when the bottom container fitting 17is lowered onto the floor 29 and into latching position. A horizontallatching under surface 82 is provided on the nose portion 80.

The latch means 61, which is formed of suitable metal is generallyplatelike in configuration and is positioned between the furcations 45of the follower 44 with the roll pin 47 extending through the arcuateslot 65.

With a view to limiting relative movement between the follower 44 andthe latch means 61 suitable stop means is employed. The stop meanscomprises a stop surface 83 on the upper arm 62 of the latch means 61for juxtaposition to a stop surface 84, FIG. 7, on the rear side of thenose portion 52 of the follower 44. In this manner the relative movementbetween the latch means and the follower 44 is controlled. It has beenpointed out previously the manner in which the relative movement betweenthe follower 44 and the latch housing 26 is controlled.

As shown in FIGS. 4 and 7 the nose portion 80 of the latch means 61extends into the vertical slot 18 of the bottom container fitting 17 andinto overlying relation with the bottom 85 of the vertical slot 18. Morespecifically the horizontal latching under surface 82 overlies thebottom 85 of the vertical slot 18 and in this manner the requiredlatching engagement with the bottom container fitting 17 is provided.

In FIG. 4 the extent that the latching under surface 82 overlies thebottom 85 of the vertical slot 18 is indicated at 86. This degree ofoverlap is ample to maintain proper latching engagement with the bottomcontainer fitting 17 despite the clearance as indicated at 43 betweenthe wall 19 and the wall 27 of the latch housing 26. The reason for thisis that the follower 44 has been biased by the springs 56 to maintainthe surface 53 of its nose portion 52 in engagement with the wall 19 ofthe bottom container fitting 17. Since the latch means 61 is mounted onthe follower 44. It accompanies the follower 44 to maintain the properlatching engagement with the bottom container fitting 17.

Referring now to FIG. 7 it will be observed that the sidewall 19 of thebottom container fitting 17 is juxtaposed to the vertical wall 27 of thelatch housing 26. However, the distance indicated at 87 of overlap ofthe horizontal latching under surface 82 with the bottom 85 of thevertical slot 18 identical with the distance 86 in FIG. 4. Thus, withinthe predetermined limits of clearance, such as the clearance 43, thesame degree of latching engagement with the bottom fitting 17 ismaintained regardless of its relative position to the respectivecontainer locking means 15.

In operation, when the container 16 is lowered into latching engagementwith the container locking means 15, the individual bottom containerfitting 17 move downwardly as indicated by arrow 90 in FIG. 14. Thelower corner horizontal the bottom container fitting 17 engages theinclined striker surface 81 and displaces the latch means 61 to theposition here shown. During this operation the latch means 61 pivotsabout axis 66 of the trunnions 67 on the shoulders 51 at the lowerdistal ends of the furcations 45 as permitted by the arcuate slot 65.This involves only a slight stressing of the coil tension spring 74. 'Onfurther downward movement in the direction indicated by arrow 90 thelower corner of the bottom container fitting 17 engages the inclinedstriker surface 54 of the follower 44 and it is displaced until itssurface 53 engages the sidewall 19 in the position shown for example ineither FIG. 4 or FIG. 7. Also the nose portion 80 is pivoted to thelatching position here shown with respect to the vertical slot 18. InFIG. 4 the roll pin 47 is positioned at the right end of the horizontalslots 48 in the walls 49 and 50 of the latch housing 26. In FIG. 7 theroll pin 47 is positioned at the left ends of these horizontal slots 48.

When a sufficient lifting force is applied to the rectangular container16 it and the bottom container fitting 17 move upwardly as indicated byarrow 91 in FIG. 15. Here the bottom 85 of the vertical slot 18 reactsagainst the horizontal latching under surface 82 which previously hadbeen held in latching position by the coil tension spring 74. Underthese circumstances the latch means 61 pivots about the axis 93 of theroll pin 47 at the left end of the horizontal slots 48. The trunnions 67are lifted from the shoulders 51 and a considerably greater extension ofthe spring 74 takes place than occurs when, as shown in FIG. 14, thebottom container fitting is moved downwardly into latching position.After the bottom container fitting 17 has been moved upwardly out ofengagement with the nose portion 52 of the follower 54 and the noseportion 80 of the latch means 61, these elements resume the positionsshown in FIG. 13 and as illustrated in the other figures, for exampleFIGS. 4 and 7.

What is claimed as new is:

1. Container securing means for a transport carrier arranged to securethereto one or more containers each having at least one bottom containerfitting with a latch receiving opening in a wall thereof, said bottomcontainer fitting being likely to have substantial clearance betweensaid wall and said container securing means, said container securingmeans comprising:

housing means for attachment to said transport carrier for underlyingeach bottom container fitting,

follower means movably mounted on said housing means,

means positioned between said housing means and said follower means tobias said follower means toward engagement with said wall of said bottomcontainer fitting, latch means movably mounted on said follower meansand means biasing said latch means into latching engagement with saidbottom container fitting at said opening therein.

2. Container means according to claim 1 wherein:

means on said housing means limits said movement of said follower means,and

means on said follower means limits said movement of said latch means.

3. Container means according to claim 1 wherein:

follower spring means reacts between said housing means and saidfollower means and biases said follower means for translatory movementrelative to said housing means, and

latch spring means reacts between said housing means and said latchmeans and biases said latch means for relative pivotal movement withrespect to said follower means and to said housing means.

4. Container means accordin to claim 1 wherein: said housing means has awa l for JUXIEPOSIIIOH to said wall of said bottom container fitting,

means translatory mount said follower means on said housing means,

said follower means has a nose portion movable relative to said wall onsaid housing means to engage said wall of said bottom container fitting,I

means pivotally mount said latch means on said follower means,

said latch means has a nose portion movable relative to said wall onsaid housing means for entering said latch receiving opening in saidbottom container fitting,

stop means on said housing means limits movement of said follower meansrelative to said housing means, and

stop means of said follower means limits pivotal movement of said latchmeans relative thereto and to said housing means.

5. Container means according to claim 4 wherein:

said nose portion on said follower means has an inclined striker surfacefor engagement by said bottom container fitting to displace saidfollower means when said bottom container fitting is lowered onto saidhousing means along said wall thereof within the limits of saidclearance, and

said nose portion on said latch means has an inclined striker surfacefor engagement by said bottom container fitting to displace said latchmeans when said bottom container fitting is lowered onto said housingmeans as aforesaid.

6. Container means according to claim 4 wherein:

said means slidably mounting said follower means on said housing meansincludes pin and slot means respectively on said follower means and saidhousing means, and

said means pivotally mounting said latch means on said follower meansincludes said pin means on said follower means and slot means on saidlatch means and shoulder means on said follower means and trunnion meanson said latch means.

7. Container means according to claim 4 wherein:

follower spring means reacts between said housing means and saidfollower means and biases said follower means for movement relative tosaid housing, and

latch spring means reacts between said housing means and said latchmeans and biases said latch means for movement relative to said followermeans and to said housing means.

8. Container means according to claim 4 wherein:

said follower means is bifurcated and has: a pin extending between itsfurcations with the ends of the pin extending into slots in said housingmeans, and latch trunnion fulcrum shoulders at the distal ends of saidfurcations, and

said latch means has: its mose portion overlying said nose portion ofsaid follower means, a body portion between said furcations of saidfollower means, a slot intermediate its end through which said pinextends, and trunnions for engaging said fulcrum shoulders.

9. Container means according to claim 4 wherein:

a pair of coil compression springs react between said follower means andsaid housing means and bias said nose portion of said follower meanstoward said wall of said bottom container fitting, and

a coil tension spring reacts between an arm of said latch meansextending from said trunnions and said housing means and biases saidnose portion of said latch means into said latch receiving opening insaid bottom container fitting.

l0. Container means according to claim 1 wherein, within the limits ofsaid clearance, the extent of latching engagement of said latch means insaid latch receiving opening in said bottom container fitting is thesame for all operative positions of said bottom container fitting onsaid housing means.

1. Container securing means for a transport carrier arranged to securethereto one or more containers each having at least one bottom containerfitting with a latch receiving opening in a wall thereof, said bottomcontainer fitting being likely to have substantial clearance betweensaid wall and said container securing means, said container securingmeans comprising: housing means for attachment to said transport carrierfor underlying each bottom container fitting, follower means movablymounted on said housing means, means positioned between said housingmeans and said follower means to bias said follower means towardengagement with said wall of said bottom container fitting, latch meansmovably mounted on said follower means and means biasing said latchmeans into latching engagement with said bottom container fitting atsaid opening therein.
 2. Container means according to claim 1 wherein:means on said housing means limits said movement of said follower means,and means on said follower means limits said movement of said latchmeans.
 3. Container means according to claim 1 wherein: follower springmeans reacts between said housing means and said follower means andbiases said follower means for translatory movement relative to saidhousing means, and latch spring means reacts between said housing meansand said latch means and biases said latch means for relative pivotalmovement with respect to said follower means and to said housing means.4. Container means according to claim 1 wherein: said housing means hasa wall for juxtaposition to said wall of said bottom container fitting,means translatory mount said follower means on said housing means, saidfollower means has a nose portion movable relative to said wall on saidhousing means to engage said wall of said bottom container fitting,means pivotally mount said latch means on said follower means, saidlatch means has a nose portion movable relative to said wall on saidhousing means for entering said latch receiving opening in said bottomcontainer fitting, stop means on said housing means limits movement ofsaid follower means relative to said housing means, and stop means ofsaid follower means limits pivotal movement of said latch means relativethereto and to said housing means.
 5. Container means according to claim4 wherein: said nose portion on said follower means has an inclinedstriker surface for engagement by said bottom container fitting todisplace said follower means when said bottom container fitting islowered onto said housing means along said wall thereof within thelimits of said clearance, and said nose portion on said latch means hasan inclined striker surface for engagement by said bottom containerfitting to displace said latch means when said bottom container fittingis lowered onto said housing means as aforesaid.
 6. Container meansaccording to claim 4 wherein: said means slidably mounting said followermeans on said housing means includes pin and slot means respectively onsaid follower means and said housing means, and said means pivotallymounting said latch means on said follower means includes said pin meanson said follower means and slot means on said latch means and shouldermeans on said follower means and trunnion means on said latch means. 7.Container means according to claim 4 wherein: follower spring meansreacts between said housing means and said follower means and biasessaid follower means for movement relative to said housing, and latchspring means reacts between said housing means and said latch means andbiases said latch means for movement relative to said follower means andto said housing means.
 8. Container means according to claim 4 wherein:said follower means is bifurcated and has: a pin extending between itsfurcations with the ends of the pin extending into slots in said housingmeans, and latch trunnion fulcrum shoulders at the distal ends of saidfurcations, and said latch means has: its mose portion overlying saidnose portion of said follower means, a body portion between saidfurcations of said follower means, a slot intermediate its end throughwhich said pin extends, and trunnions for engaging said fulcrumshoulders.
 9. Container means according to claim 4 wherein: a pair ofcoil compression springs react between said follower means and saidhousing means and bias said nose portion of said follower means towardsaid wall of said bottom container fitting, and a coil tension springreacts between an arm of said latch means extending from said trunnionsand said housing means and biases said nose portion of said latch meansinto said latch receiving opening in said bottom container fitting. 10.Container means according to claim 1 wherein, within the limits of saidclearance, the extent of latching engagement of said latch means in saidlatch receiving opening in said bottom container fitting is the same forall operative positions of said bottom container fitting on said housingmeans.